Accelerator
DTL4 installation
Preparations are ongoing to start the installation of Drift Tube Linac tank 4 in the normal conducting linac. A small vacuum leak was repaired and a water manifold installed on top of the tank.
Power sources
Power tests, including klystrons in medium beta cells and the RF power stations feeding the Spoke section of the linac, are ongoing.
Power tests in the Normal Conducting Gallery have also restarted in preparation for the next phase of beam commissioning to include Drift Tube Linacs 2-4.
Upgrades to the E-bends of the waveguide system, carrying RF power from the gallery-side to the Accelerator via the stubs, are ongoing.
Cryogenics
Leak testing of the Cryogenic Distribution System is in progress, with detected leaks subject to repair. The entire system, from cryoplant to end box and back, need to be leak tights before proceeding with the installation of cryomodules to the valve boxes.
Cryomodules
Medium beta cryomodule CM07 is being prepared for testing inside the on-site test bunker. The objective is to have seven out of a total nine medium beta modules fully tested and ready for installation before the end of this year. 2023 will start with cooldown and tests of the very first high beta cryomodule.
Nine out of 13 double-cavity spoke cryomodules are in the ESS workshop building, made ready for installation. Remaining four spoke modules will be tested at the Freia lab at Uppsala University and delivered to ESS before the end of 2022.
Target
Representatives from Thune Eureka, subcontractor to ESS Bilbao, have been on site this week to assist in adjustment works to fit the shaft onto the Target Wheel inside the Mock-up and Test Stand in the Transport Hall.
The full 12,3-metre long Proton Beam Drift Room pipe is in place in the narrow space connecting the Accelerator to Target building with the remote clamp inside the Monolith connection cell. Precise alignment and vacuum tests are next.
Instruments
Experimental Hall 1
The ESTIA Selene guide 2 is in place on a steel support structure.
Light Shutter System frames have been fitted inside the south sector of the bunker, with basement works ongoing.
Experimental Hall 2
Fitting of raceways for electrical installations under the LOKI detector tank is in progress.
In the west corner of the D03 hall a chopper workshop building is under construction.
BIFROST bandwidth chopper
The very first neutron chopper for ESS has been installed for instrument BIFROST. The 14 hertz double disc chopper has been placed in the middle of the 160-metre-long neutron guide for the instrument, in the E02 beamline gallery.
Choppers are devices placed along the instrument beamlines for each instrument. A rotating disc with slits will let through only the desired range of the neutron pulse, suitable for the instrument and experiment conducted. Phasing of choppers is done with the ESS timing system, synchronised with the proton beam at 14 pulses per second.
